Video signal processing device and display

1. A video signal processing device comprising: first and second input terminals; a size changer configured to change an image size of an image to be displayed based on a video signal input from the second input terminal and to convert the video signal input from the second input terminal to a progressive signal; a video input circuit configured to convert the video signal input from the second input signal into a video signal that has a same color format as that of a video signal input from the first input terminal; a mixer configured to mix the video signal input from the first input terminal with a video signal that has passed through the size changer; and an output terminal configured to output a video signal arising from mixing by the mixer, wherein the size changer includes a memory controller that controls reading and writing data from a frame memory of the size changer under the control of a CPU, wherein the size changer further determines a displaying position of the converted video signal in a display screen, wherein the video signal processing device is an attachable/detachable component connected with a plurality of the same video signal processing devices in a hierarchy manner, wherein the number of the plurality of the same video signal processing devices is changed in accordance with a number of multi-screens that are used in the display screen, wherein the first input terminal is connected directly to the mixer with no image processing modules in between so that the video signal input from the first input terminal is input to the mixer without alteration, and wherein when an image reduction processing is executed for a size change, a signal for a black background is output for an image part other than a reduced video part.

2. The video signal processing device according to claim 1 , wherein the size changer executes processing for a video signal input from the second input terminal in synchronization with a video signal input from the first input terminal.

3. A display comprising: a video signal processor configured to be formed by cascading a plurality of modules to each other, each of the modules including first and second input terminals, a size changer that changes an image size of an image to be displayed based on a video signal input from the second input terminal, a mixer that mixes a video signal input from the first input terminal with a video signal that has passed through the size changer, and an output terminal that outputs a video signal arising from mixing by the mixer; and a display unit configured to display the same number of screens as the number of the modules on one display screen in accordance with a mixed video signal output from the module at a last stage in the video signal processor, wherein the size changer includes a memory controller that controls reading and writing data from a frame memory of the size changer under the control of a CPU, wherein the size changer further determines a displaying position of the converted video signal in a display screen, wherein the video signal processing device is an attachable/detachable component connected with a plurality of the same video signal processing devices in a hierarchy manner, wherein the number of the plurality of the same video signal processing devices is chanced in accordance with a number of multi-screens that are used in the display screen, wherein the first input terminal is connected directly to the mixer with no image processing modules in between so that the video signal input from the first input terminal is input to the mixer without alteration, and wherein when an image reduction processing is executed for a size change, a signal for a black background is output for an image part other than a reduced video part, wherein the size changer further changes the video signal input from the second input terminal to a progressive signal, and wherein each of the modules further includes a video input circuit configured to convert the video signal input from the second input signal into a video signal that has a same color format as that of a video signal input from the first input terminal.

4. The display according to claim 3 , wherein the size changer executes processing for a video signal input from the second input terminal in synchronization with a video signal input from the first input terminal.